Vortex gun can shoot pepper spray at 90 mph

Those in the defense business, for obvious reasons, are increasingly getting a lot of flack for producing what some would consider instruments of death. That's why, as of late, there's been a growing emphasis on developing non-lethal weapons that would allow law enforcement to quell dangerous situations such as riots without having to resort to using potentially deadly force.

The vortex ring gun, which fires short, circular pulses of high pressure gas instead of bullets, has long been considered one of the most promising technologies. However, field tests have shown that prototypes lacked sufficient knock-down force to be feasible for the military and other agencies. Now, researchers at a company called Battelle claim they have discovered a new way to enable the technology to be highly effective.

But first, let's take a deeper look at how a vortex gun or cannon works. Instead of bullets, the weapon's firing mechanism forces air or some other gas at high velocity down the cylinder. The ring is generated when the friction of the cylinder wall causes a thin layer of the gas to roll forward on itself like a donut. Imagine a tornado formed into a donut shape. The ring revolves on itself while traveling out the cylinder, maintaining that stability for long distances. Depending on the size of the gun, Battelle says they have data showing that a ring vortex can exit a generator at 90 miles per hour and travel at a constant speed of at least 60 mph for more than 50 yards.

Vortex rings are also extremely stable even in a cross wind. Scientists believe the dynamics of the propagating ring cause it to turn into the cross wind and resist being blown away or broken up, says researcher Lynn Faulkner.

While this doesn't deliver the kind of brute physical force necessary to take people out, it's enough to deliver a projectile comprised of pesticides or mace directly at an intended target. And, by adding an electrical charge, the rings would have a strong "clinging effect" to the surface of objects once it disperses.

"What happens to the electric charge is that it gets attracted to the smoke particles," Jim Dvorsky, Battelle's product development leader, told InnovationNewsDaily. "That makes the smoke particles migrate to any surface that's available — furniture, ceiling, floor."

The electrical charge can also cause surrounding smoke to clump up and move away, which means the gun can be useful tool to clear a path for firefighters as they navigate a burning building.

"Firefighters won’t go into a building unless they can see their way," Faulkner said. "So if they could fire a vortex ring of ionized air into a space—down a hallway or up some stairs—and clear smoke rapidly, it would really help."

Battelle, which desribes itself as "committed to using science and technology as a positive force for change," has filed for a patent for the technology and plans to further tweak the electrical charge so that the rings can remain stable over longer distances.